New findings from a study by Drexel and Arizona State show a Taser shock can produce serious short-term impairment in a person’s ability to remember and process information. Some participants — otherwise healthy, active college students — showed cognitive declines comparable with dementia. This first-of-its-kind study is the first time the Taser has been submitted to a major randomized clinical trial that wasn’t an in-house venture, and its findings raise serious questions about the ability of tased subjects to understand their rights at the point of arrest.

The Drexel/ASU researchers found that receiving a shock from a Taser reliably produced a decrease in cognitive function from the just-above-average level of a fit, active college student to the average level of a 79-year-old adult. “The findings of this study have considerable implications for how the police administer Miranda warnings,” said Robert Kane, professor and director of the Criminology and Justice Studies Department at Drexel, and one of the study’s principal investigators. “We felt we had moral imperative to fully understand the Tasers’ potential impact on decision-making faculties in order to protect individuals’ due process rights.”

How do you control for getting shot by a Taser, anyway? One group of participants punched a punching bag instead of getting zapped, to “simulate the heightened physical state” they’d be experiencing during an actual police encounter. One group experienced no shocks and no punching, and another experienced just the Taser. And just to make sure, the positive control group punched the punching bag and got Tased. You know, for science.

Tased participants showed the greatest effect on their access to language, as measured by the Hopkins Verbal Learning Test. The results indicate Taser exposure caused significant reductions in verbal learning and memory. But the researchers took care to point out that the participants in the study were largely recruited from universities — healthy, high-functioning individuals who were accustomed to test-taking, and who were sober and drug-free at the time of their Tasing.

In the field, in an actual arrest situation, “We would expect ‘typical’ suspects – who may be high, drunk, or mentally ill and in crisis at the time of exposure – to experience even greater impairment to cognitive functioning as the result of Taser exposure,” said Kane. Fully a quarter of both Taser groups showed symptoms of cognitive decline and other emotional distress, with some subjects exhibiting a short-term syndrome comparable to dementia that lasted about an hour.

The study was funded by the Department of Justice, and the upshot is that the we need a public dialogue about how to use the Taser for lawful, everyday policing. The researchers ask: “What would it cost police to wait 60 minutes after a Taser deployment before engaging suspects in custodial interrogations?”